In Search of Sustainable Economy Definition: A Qatari Perspective

Abstract

This paper aims to assess Sustainable Economy (SE) features and validate them by using sustainability experts residing in Qatar to suggest an expanded and improved definition of SE. Fifteen features of SE have been identified via a comparative literature review and validated by sustainability experts in Qatar. The study significantly strengthens and validates the features of SE and provides analysis of some of these features by the authors. The paper suggests that SE should be defined as “a value-based, dynamic, and balanced economic system that meets the needs of all living species today while remaining within ecological and social boundaries, without compromising the system’s capacity to meet all future needs of all living species”. This is the only paper that uses Qatari experts to research SE features. The limitation of the research is the inclusion of a small sample size of experts within Qatar due to the limited number of experts in the field of sustainability and their willingness to participate.

1. Introduction

The paper attempts to answer the question of what a Sustainable Economy (SE) is and what its features are. The paper’s objective is to identify the main features of SE and provide a more encompassing definition for SE according to the literature by global sustainability researchers, and validation of these features by sustainability experts in Qatar. The reason for focusing on experts in Qatar is that the paper’s authors are based in Qatar and focus on economics and sustainability. Qatar is ambitious in achieving Sustainable Development (SD). For this reason, a more sustainable economic development might be a prerequisite for achieving SD. It contributes to the literature on SE by identifying core SE features and defining SE.

The paper could open new horizons for further research, solidifying the effort toward achieving SD. By providing a clearer understanding of SE and its key features, this study enables more effective decision-making and planning for sustainable development, ultimately supporting the global pursuit of the SDG.

The significance and originality of the paper are derived from the opinions of sustainability experts in Qatar on the features of SE. The research starts with a literature review and comparative analysis to determine the main features of SE. To our knowledge, this is the only paper that bases its findings on Qatari sustainability experts. The work also advances the subject by seeking to offer new definitions of SD and SE.

2. Comparative Review and Analysis of Literature

2.1. Conventional Economy (CE)

After World War II, linear growth was believed to produce even more growth [1]. Economic growth was also considered equivalent to economic development [2]. However, it was found that growth alone and actions for growth were insufficient to meet real development needs [3].

During the 1970s, maintaining linear growth was considered unsustainable due to economic shocks and challenges [4]. It was unsustainable because it accidentally exceeded ecological limits where balance was lost: (1) rapid and limitless growth; (2) there was a barrier where the system could not be sustained; and (3) there was a delay in the system’s ability to respond and provide feedback to keep the system within limits [5], causing a divide between society members and the global community while the ecological debt of the developed world was burdening developing societies [6]. A good example is the inequality between and within developed, developing, and underdeveloped societies. The global division increases the growing gap between the rich and the poor and the suffering of the needy [7].

2.2. Sustainable Economy (SE)

Sustainable economics is not yet an academic field; however, the discipline uses knowledge from ecological economics, environmental economics, politics, and other fields to develop the concept of SE [8]. According to ref. [9], the discipline of economics significantly impacted the development of the concepts of sustainability and SD.

According to ecological economists, including Martinez-Alier, the failure of CE [10] and environmental economics to address environmental challenges [11] led to the development of ecological economics. The debate between environmental economists and ecological economists shows enormous differences between them. For example, there is a claim that environmental economists are economizing nature while ecological economists are ecologizing the economy [12]. This debate led to a spectrum of sustainability scales ranging from very weak to very strong. Natural and manufactured capital are not direct replacements; rather, the conservation of natural resources should take precedence over economic growth and maintaining the status quo [13]. Resources are finite; no price can reflect their value because the economy is based on value exchange (cost–benefit). However, the environment is a physical–biological process [14].

Thus, it is a challenging task to define SE; even though there is a perception of it [15], it has been identified by several names [16], including the green economy, sharing economy, circular economy, and the no-growth economy as part of the post-growth economy.

2.3. Conventional Economy (CE) vs. Sustainable Economy (SE)

SE is circular, restorative, and regenerative [17], while CE is growth-dependent. In addition, SE is needed to respond to long-term social and environmental challenges using innovation and creativity while meeting current and future generations’ needs within ecological limits. However, while SE focuses on needs essential for survival and development, CE focuses on consumption and excess production to ensure continuous growth.

On the other hand, CE is focused on growth with no regard for justice and equity since it is based on self-interest and utility maximization [18]. It attempts to maximize the living standard without regard to justice, equity, or ecological limits by achieving maximum economic growth [19].

An SE differs philosophically from CE in the regard that it considers natural capital (air, land, and water) as a common heritage that should be shared fairly among current and future generations with a cost to use it to prevent limitless use and exploitation by few who have the tools and urgency [20]. Additionally, SE is a value-based economic system that achieves sustainable economic prosperity within ecological limits [21] through innovation [22] and entrepreneurship without growth [18]. This is carried out in a just and equitable manner among people within the same country, among countries, and among current and future generations [23] while developing the economy through a resilient, low-carbon economy with enterprises and people contributing positively to SD and meeting society’s needs within ecological limits [24]. Moreover, SE holds that social participation is vital by having both society and government play a significant role in planning [8] for long-term prosperity and well-being [25] without jeopardizing the opportunities and resources available for future generations [15].

3. Methodology

The research methodology involves several steps to answer the question of what SE is and its significant features. First, we conduct a literature review to identify SE features. Next, we analyze the similarities and differences between SE and CE to better understand SE’s unique aspects. Next, we share the identified features with sustainability experts to evaluate their agreement on the relevance and importance of each feature. Finally, we refine the list based on expert feedback and suggest a definition. Two methods of reasoning could be used to better comprehend SE based on the reviewed literature. First, we use deductive reasoning to examine the literature for suggested definitions and reduce them to simple ones. Second, we apply inductive reasoning to SE’s features and attempt to construct a definition. Furthermore, a contrast and comparative analysis would further clarify the differences between the concepts of SE and CE. Figure 1 outlines the research process.

To evaluate the importance of SE features based on experts’ ranking, a null hypothesis is developed, which states the feature is not important by setting the mean of the ranking to zero (H0: μ = 0) and the alternative hypothesis, that the mean of the ranking is greater than zero (H1: μ > 0), means that the feature is important. Similarly, for evaluating the relevance of SE features, the weight by experts is taken as representative of relevance and the null hypothesis that the mean ranking is zero (H0: μ = 0), which means not relevant, and the alternative hypothesis that the mean ranking is greater than zero (H1: μ > 0) indicates relevance based on the weights given by the experts. We conduct a sample Student t-test to both approve or disprove the importance and relevance of each SE based on a 99% level of confidence. The deleted features were ranked zero by experts to represent the deletion; however, this may have created some biases by lowering the average, which will be addressed later. The statistical packages used for the analysis are JASP (Jeffreys’s Amazing Statistics Program) and Microsoft Excel, which are intuitive and sufficient for such research.

Table 1. Comparative features, attributes, and goals of CE vs. SE.

Features
Conventional Economy	Sustainable Economy
Economy-focused	Sustainability-focused
Linear	Circular
Growth beyond natural limits	Economic activity within ecological limits
Greed	Fairness and equity
Vulnerable	Resilient
Short-Term focus	Long-term view
Standard-of-living focused	Well-being focused
Exclusive	Inclusive
Extractive	Knowledge-based economy
Unequal distribution	Balanced
Greed	Social development
Unaccounted externalities	Internalization of externalities
Static	Dynamic
Resource-based economy	Creative and innovative
Industrial	Entrepreneurial
Minimal social aspects	Social development

compares the significant features of CE and SE based on the comparative analysis of the literature review. Again, it is clear that SE and CE features are hugely different. SD considers human development and sustainability as part of measuring sustainability [26], and there is a clear shift away from focusing solely on the economic dimension towards more inclusion of social and ecological dimensions [27].

In order to confirm the SE features based on comparative analysis with CE attributes, a group of 100 experts was identified. Identifying these experts involved searching for relevant individuals in academic institutions and government bodies responsible for planning and reporting. However, it is essential to note that finding such experts in Qatar can be challenging and relies heavily on networking and their willingness to participate. The challenge was to identify and engage sustainability experts, especially since such experts are very limited in Qatar and many of them are difficult to engage due to their commitments or lack of willingness, and for other considerations. Therefore, the selection process for the sample of experts was based on their approachability and availability, which may be considered a limitation. Despite this, the study included 32 experts from various backgrounds, including academicians, governmental representatives, and industry/business practitioners dealing with economics, finance, governance, and development issues.

The process must be simple and convenient to engage the experts in Qatar. Too-long interviews and long questionnaires might discourage them from participating. Therefore, the experts were contacted through different means of communication based on their preference to provide feedback. The experts were contacted through one-on-one interviews, email exchanges, or both, and 22 of them, or around 70%, responded positively (Figure 2).

Some of these experts are sustainability researchers and scholars, and others are experts in economic development and planning, development strategy, innovation, finance, sustainable investment, and social responsibility.

Table 2. Experts and Means of Collecting Feedback.

Experts and Means of Collecting Feedback
Experts Categories	Physical Session	Interview	Email	WhatsApp	Total	%
Sustainability Researchers	11	0	4	0	15	68%
Economics and Development	0	1	0	4	5	23%
Sustainability Investors	0	2	0	0	2	9%
Total	11	3	4	4	22	100%
%	50%	14%	18%	18%	100%

demonstrates that a physical session was held with 11 sustainability experts. The physical session involves 50% of all respondents. The features of SE were shared with the experts, and after discussion, they were requested to rank and add new features based on importance and relevance to SE. Importance was measured in terms of ranking among the identified sustainability features through the literature review.

Some experts explained that “growth within natural limits” and setting “ecological limits” are similar and should be combined, while other experts considered them different. To resolve this issue, both were combined under one feature: “economic activity within ecological limits”. Based on this adjustment, rankings were adjusted by selecting the highest ranking of the two and deducting one of the subsequent ranks. If the weights differ, the average weight is used; otherwise, the exact weight is used.

Furthermore, 13 experts were emailed; however, only 4 responded, representing approximately 31% of the emailed experts and approximately 18% of all respondents. Finally, five experts were approached via WhatsApp; however, only four responded, representing 80% of the experts contacted and approximately 18% of the respondents.

In addition, three experts were invited for interviews and ranking exercises, and all responded positively. Some of the interviewees expressed that the list provides almost comprehensive SE features. Some expressed that SE features should have global aspects; however, the interviewees provided no clear vision or definition. One suggested that global citizenship could be part of global aspects, which might require further research.

4. Results and Discussions

The feedback from the experts validated the fifteen features identified by the literature review and the comparative analysis to be relevant and important. All the experts agreed that economic activity within ecological limits, resilient, long-term view, well-being-focused, knowledge-based economy, social development, entrepreneurship, and creative and innovative are part of the SE features (Figure 3). While 21 experts (approximately 95.5%) agreed that circular, fairness and equity, inclusive, balanced, internalization of externalities, and dynamic are all part of SE features, 20 experts (approximately 91%) agreed that sustainability-focused is among SE features. On the other hand, some experts suggested including new features such as global aspects, social awareness, low cost, security, political perspective, and integration to the list of sustainability features.

One expert attempted to explain the global aspect by establishing globalized commitment and global action, while others believed that global action starts locally. Although these opinions necessitate further studies and analysis beyond the scope of this study, it is essential to highlight that any feature of SE should be scalable to a global level but could be implanted locally at different proportions based on domestic needs.

Another expert highlighted that, if well-being is ranked highly and achieved, this could implicitly include social development and many other social aspects. This is a valuable insight that also needs further study and analysis. In addition, another expert also mentioned social awareness as a new feature that could also be part of social development.

With a 99% confidence level and due to their extremely low p values (less than 0.001), there was sufficient evidence to reject the null hypothesis and support the alternative hypothesis. According to experts, this entails economic activity within ecological limits, resilient, long-term view, well-being-focused, knowledge-based economy, social development, creative and innovative, entrepreneurship, circular, fairness and equity, inclusive balanced, internalization of externalities, dynamic, and sustainability-focused. At the same time, there is insufficient evidence to support the rest of the suggested SE features due to either high p values or small sample size (

Table 3. Student t-test Results for Ranking.

One Sample t-Test
	t	df	p
Sustainability-focused	5.246	19	<0.001
Circular	6.924	20	<0.001
Dynamic	10.137	20	<0.001
Economic activity within ecological limits	6.198	21	<0.001
Internalization of externalities	9.362	20	<0.001
Knowledge-based economy	7.51	21	<0.001
Entrepreneurship	12.292	21	<0.001
Long-term view	9.854	21	<0.001
Well-being-focused	9.489	21	<0.001
Creative and innovative	12.128	21	<0.001
Balanced	10.231	20	<0.001
Fairness and equity	7.69	20	<0.001
Inclusive	8.508	20	<0.001
Resilient	8.333	21	<0.001
Social development	10.968	21	<0.001
Social awareness	NaN
Global aspect	2.12	2	0.168
Low cost	NaN
Political perspective	NaN
Security	NaN
Integrated	NaN
Externalities pricing	NaN

).

While ranking is important to prioritize these 15 SE features, the question of what measure of central tendency should apply remains.

Table 4. Ranking Descriptive Statistics.

Sustainability Features	Mode a	Median	Mean	Std. Dev.	Variance	Range	Min	Max
Sustainability-focused	1.00	2.50	4.23	4.01	16.09	13.00	0.00	13.00
Circular	2.00	6.00	5.86	4.18	17.46	13.00	0.00	13.00
Dynamic	3.00	10.00	8.77	4.50	20.28	15.00	0.00	15.00
Economic Activity within Ecological Limits	1.00	5.00	6.36	4.82	23.20	14.00	1.00	15.00
Internalization of externalities	15.00	8.00	8.73	4.78	22.87	15.00	0.00	15.00
Knowledge-based economy	13.00	9.00	7.86	4.91	24.12	13.00	1.00	14.00
Entrepreneurial	12.00	12.00	10.41	3.97	15.78	13.00	2.00	15.00
Long-term view	5.00	7.00	7.68	3.66	13.37	13.00	2.00	15.00
Well-being-focused	8.00	8.00	7.68	3.80	14.42	14.00	2.00	16.00
Creative and innovative	14.00	9.50	10.05	3.89	15.09	12.00	4.00	16.00
Balanced	8.00	8.00	7.96	4.05	16.43	15.00	0.00	15.00
Fairness and equity	3.00	6.00	6.68	4.34	18.80	15.00	0.00	15.00
Inclusive	13.00	8.50	7.82	4.65	21.58	15.00	0.00	15.00
Resilient	6.00	6.00	6.82	3.84	14.73	12.00	1.00	13.00
Social development	7.00	9.00	8.50	3.64	13.21	12.00	2.00	14.00
Social awareness	5.00	5.00	5.00	NaN	NaN	0.00	5.00	5.00
Global aspect	3.00	6.00	8.33	6.81	46.33	13.00	3.00	16.00
Low cost	7.00	7.00	7.00	NaN	NaN	0.00	7.00	7.00
Political perspective	17.00	17.00	17.00	NaN	NaN	0.00	17.00	17.00
Security	16.00	16.00	16.00	NaN	NaN	0.00	16.00	16.00
Integrated	17.00	17.00	17.00	NaN	NaN	0.00	17.00	17.00
Externalities pricing	6.00	6.00	6.00	NaN	NaN	0.00	6.00	6.00

^a More than one mode exists; only the first was reported.

demonstrates that ranking according to mode or median is impractical since several SE features share the same mode and median. The most practical alternative is to rank based on the arithmetic mean. However, there are two issues with arithmetic mean: First, using a zero rank to represent deleted features that may have skewed the ranking mean.

Second, the similar arithmetic means of well-being-focused and knowledge-based economies. A formula was created to adjust for the bias caused by using zero for deleted SE features by deducting the average rank score from the total number of SE features (

Table 5. Ranking of SE Features.

Rank	Sustainability Features	Mode	Median	Mean	Score
1	Sustainability-focused	1.00	2.50	4.23	10.77
2	Circular	2.00	6.00	5.86	9.14
3	Economic Activity within Ecological Limits	1.00	5.00	6.36	8.64
4	Fairness and equity	3.00	6.00	6.68	8.32
5	Resilient	6.00	6.00	6.82	8.18
6	Long-term view	5.00	7.00	7.68	7.32
7	Well-being-focused	8.00	8.00	7.68	7.32
8	Inclusive	13.00	8.50	7.82	7.18
9	Knowledge-based economy	13.00	9.00	7.86	7.14
10	Balanced	8.00	8.00	7.96	7.05
11	Social development	7.00	9.00	8.50	6.50
12	Internalization of externalities	15.00	8.00	8.73	6.27
13	Dynamic	3.00	10.00	8.77	6.23
14	Creative and innovative	14.00	9.50	10.05	4.96
15	Entrepreneurial	12.00	12.00	10.41	4.59

). According to this ranking method, sustainability-focused ranks first, circular second, and economic activity within ecological limits third. On the other hand, the bottom three are entrepreneurship last, creative and innovative second-last, and dynamic at the 13th rank.

The weight given to each SE feature is important because it signifies the relevance of each feature. The ranking part was straightforward for most experts; however, the weighting exercise was more challenging. Some preferred to add up all the identified features to 100%, while others preferred to weigh each feature out of 100%. The experts were given both options for convenience, and then the weights were adjusted to add up to 100%. The purpose of the weight was to identify how relevant the feature is to SE. Zero percent weight would imply no relevance at all.

Table 6. Weight Descriptive Statistics.

Sustainability Features	Mode a	Median	Mean	Std. Dev	Variance	Range	Min	Max
Sustainability-focused	6.00	8.00	8.14	4.54	20.60	20.00	0.00	20.00
Circular	6.00	7.00	8.00	4.67	21.81	25.00	0.00	25.00
Dynamic	7.00	6.00	6.32	3.36	11.28	15.00	0.00	15.00
Economic activity within ecological limits	3.00	7.00	7.68	4.01	16.04	17.00	3.00	20.00
Internalization of externalities	7.00	6.00	5.91	2.20	4.85	9.00	1.00	10.00
Knowledge-based economy	6.00	6.00	6.73	3.45	11.92	13.00	2.00	15.00
Entrepreneurial	5.00	5.00	5.18	2.26	5.11	10.00	1.00	11.00
Long-term view	5.00	6.50	6.55	1.92	3.69	8.00	2.00	10.00
Well-being-focused	7.00	6.00	5.91	2.16	4.66	11.00	1.00	12.00
Creative and innovative	5.00	5.00	5.14	1.64	2.70	8.00	1.00	9.00
Balanced	5.00	6.00	6.23	2.94	8.66	15.00	0.00	15.00
Fairness and equity	7.00	6.50	5.91	2.47	6.09	10.00	0.00	10.00
Inclusive	6.00	6.00	6.00	2.81	7.91	11.00	0.00	11.00
Resilient	7.00	7.00	7.00	1.93	3.71	9.00	4.00	13.00
Social development	7.00	6.00	6.23	3.70	13.71	19.00	1.00	20.00
Social awareness	9.00	9.00	9.00	NaN	NaN	0.00	9.00	9.00
Global aspect	6.00	7.00	7.33	1.53	2.33	3.00	6.00	9.00
Low cost	6.00	6.00	6.00	NaN	NaN	0.00	6.00	6.00
Political perspective	7.00	7.00	7.00	NaN	NaN	0.00	7.00	7.00
Security	7.00	7.00	7.00	NaN	NaN	0.00	7.00	7.00
Integrated	7.00	7.00	7.00	NaN	NaN	0.00	7.00	7.00
Externalities pricing	8.00	8.00	8.00	NaN	NaN	0.00	8.00	8.00

^a More than one mode exists; only the first was reported.

shows the descriptive statistics for expert-assigned SE feature weights.

Based on the foregoing, a null hypothesis was developed, assuming that the mean weight is equal to zero percent (H0: μ = 0), and an alternative hypothesis was developed, assuming that the weighted mean is greater than zero (H1: μ > 0), indicating that there is significant relevance. A Student t-test on the weight of SE features was conducted. Based on the results, we can reject the null hypothesis with a 99% confidence level due to their extremely low p values (less than 0.001) and support the alternative hypothesis, implying that economic activity within ecological limits, resilient, long-term view, well-being-focused, knowledge-based economy, social development, creative and innovative, entrepreneurship, circular, fairness and equity, inclusive balanced, internalization of externalities, dynamic, sustainability-focused, and a global aspect are relevant SE features. At the same time, there was insufficient evidence to support the remaining suggested SE features due to the small sample size (

Table 7. Student t-test Weight Results.

One Sample t-Test
Sustainability Features	t	df	p
Sustainability-focused	8.408	21	<0.001
Circular	8.035	21	<0.001
Dynamic	8.826	21	<0.001
Economic activity within ecological limits	8.997	21	<0.001
Internalization of externalities	12.587	21	<0.001
Knowledge-based economy	9.138	21	<0.001
Entrepreneurial	10.754	21	<0.001
Long-term view	15.986	21	<0.001
Well-being-focused	12.842	21	<0.001
Creative and innovative	14.676	21	<0.001
Balanced	9.925	21	<0.001
Fairness and equity	11.234	21	<0.001
Inclusive	10.01	21	<0.001
Resilient	17.036	21	<0.001
Social development	7.889	21	<0.001
Social awareness	NaN
Global aspect	8.315	2	0.007
Low cost	NaN
Political perspective	NaN
Security	NaN
Integrated	NaN
Externalities pricing	NaN

).

Table 8. Weight Ranking.

Relevance	Sustainability Features	Mode	Median	Mean
1	Sustainability-focused	6.00	8.00	8.14
2	Circular	6.00	7.00	8.00
3	Economic activity within ecological limits	3.00	7.00	7.68
4	Resilient	7.00	7.00	7.00
5	Knowledge-based economy	6.00	6.00	6.73
6	Long-term view	5.00	6.50	6.55
7	Dynamic	7.00	6.00	6.32
8	Balanced	5.00	6.00	6.23
9	Social development	7.00	6.00	6.23
10	Inclusive	6.00	6.00	6.00
11	Internalization of externalities	7.00	6.00	5.91
12	Well-being-focused	7.00	6.00	5.91
13	Fairness and equity	7.00	6.50	5.91
14	Entrepreneurship	5.00	5.00	5.18
15	Creative and innovative	5.00	5.00	5.14

shows the top three in terms of mean weight out of 100: sustainability-focused, circular, and economic activity within ecological limits. Moreover, the bottom three are creative and innovative, entrepreneurship ranked 15th, fairness and equity ranked 14th and well-being-focused ranked 13th.

Comparing both ranking and weight tables side-by-side (

Table 9. Comparison of Weight vs. Rank for the proposed sustainability features based on expert evaluations and feedback (Green = exact match, yellow = difference within one rank, red = difference of more than one rank, and orange = unique to this list).

Weight	Sustainability Features	Rank	Sustainability Features
1	Sustainability-focused	1	Sustainability-focused
2	Circular	2	Circular
3	Economic activity within ecological limits	3	Economic Activity within Ecological Limits
4	Global Aspect	4	Fairness and equity
5	Resilient	5	Resilient
6	Knowledge-based economy	6	Long-term view
7	Long-term view	7	Well-being-focused
8	Dynamic	8	Inclusive
9	Balanced	9	Knowledge-based economy
10	Social development	10	Balanced
11	Inclusive	11	Social development
12	Internalization of externalities	12	Internalization of externalities
13	Well-being-focused	13	Dynamic
14	Fairness and equity	14	Creative and innovative
15	Entrepreneurial	15	Entrepreneurial
16	Creative and innovative

), the table has been color-coded to show the matching ranking of features in terms of importance and relevance. Green indicates an exact match in ranking, yellow indicates a difference within one rank, red indicates a difference of more than one rank, and orange indicates that the features are not present in the other ranking list. The top three on both lists are identical, as are the 5th, 12th, and 15th ranks, which correspond to resilient, internalization of externalities, and entrepreneurship. This shows that around 38% of the rankings in importance and relevance are identical. Furthermore, long-term view, balanced, social development, and creative and innovative are within one rank disparity of approximately 25% of the ranked features. For the rest, there seems to be a huge disparity between ranks and relevance (approximately 31%). On the other hand, the global aspect (around 6% of the features) is considered relevant; however, there is not enough evidence to support its importance.

According to sustainability experts, there are sixteen relevant SE features, of which fifteen are important. Although these features are not comprehensive, they provide the core features for SE identified by the literature review and verified by experts in Qatar.

4.1. Analysis of Sustainable Economy Features

Based on the validation by sustainability experts, the fifteen features identified by the literature review and comparative analysis have been confirmed. Still, it has to be known that even the experts have different perceptions of these features. Each feature by itself is a broad concept and not easy to define and might need research by itself, but this is beyond the scope of this study. For example, “Sustainability-focused” is a challenging feature to define since sustainability is a multidisciplinary concept and each field of sustainability has its own concept. For an economist, the priority is to sustain the economy, which makes environmental challenges secondary to sustainability, leading to the adoption of weaker forms of sustainability. On the other hand, an environmental scientist would focus on the environment and would not accept a weak form of sustainability. Therefore, defining the features of SE is just the beginning because the features themselves require further research and analysis.

Moreover, the circular economy concept is also challenging to define. For example, some use the 3Rs, and others use 4Rs or 5Rs: Reduce, Reuse and Recycle. Some would add Refuse, and others would add Repurpose and Repair. Whether it will expand to 10Rs or not does not matter much, as the important concept here is the expansion of the material life cycle. The authors of this research believe that the concept of circularity could be applied not just to the material life cycle. Still, it could be more valuable if applied to ideas fostering innovation and creativity. Reducing, reusing, and recycling ideas from one field to another could lead to innovation and technological breakthroughs.

Economic activity within ecological limits requires first determining the ecological limit and then how to measure it to ensure it is not being violated. Such questions require a lot of work and could lead to different answers. For example, should the ecological limit be calculated at the national or global level, or is it based on per capita emission or emission per one dollar of GDP? These are challenging questions that require further research and discussion. This paper aims to confirm the features of SE to open the door for such questions to be answered in the future.

The question of what is fair and equitable must go together since total equality might lead to injustice. People should be equitable regarding human rights, healthcare and education, but differentiated in their contribution to society. The higher the value of contribution to society, the higher the reward should be to arrive at a fair and just outcome. Adding inclusivity to this discussion is essential since no one should be excluded from the concept of fairness and equity, citizenship rights, human rights, healthcare, education, and a minimum standard of living. Furthermore, social development is important for SE, a developed society in terms of education, awareness, health and well-being could be more capable of making better sustainability decisions and better evaluating its costs and benefits.

Another challenging feature to define is the concept of resilience. For example, for economists, economic resilience is the top priority, while for environmentalists, environmental and ecological resilience might be the top priority. Social resilience is critical to societal transformation. The authors believe that economic resilience and environmental resilience require social resilience. Transformation to SE could be more challenging without resilience.

A long-term view should be adopted in all sustainability aspects, whether economic, social, or environmental. One of the challenges of achieving SE is the costs of transformation could be high in the short-term view, but the reward could be much more compensating in the long term. The current economic paradigm only focuses on short-term reporting such as monthly, quarterly, and annual reports. Furthermore, countries should plan for the long term, such as having national strategies and visions that try to achieve long-term goals. This may also put forward the alignment of national goals with SDG and global sustainability goals. These alignments might also cause challenges since societies face different social, economic, and environmental situations. Balancing internal challenges among different spheres of sustainability and domestic and global priorities complicates the decision-making process. A balance must be struck at the domestic and global levels.

The above are only a few examples of the challenges facing sustainability experts. The bottom line here is that identifying the features of SE is important, but they also pose more challenges in terms of defining the features themselves. By confirming these features, this paper is opening the door to define SE better and propose the boundaries of the underlying concepts behind these features.

4.2. Suggested Definition for Sustainable Economy

Based on the comparative literature review, we can rely on deductive reasoning to propose an improved or alternative definition for SE consistent with SD. Starting with the Brundtland report, which is the most frequently used definition of SD: “Development that meets the needs of the present without compromising the ability of future generations” [9,28] is a good place to start to ensure that any definition of SE would be within the context of SD. One could argue that the priority is to meet the current generation’s needs since we do not know the needs of future generations or what mandate we have to make decisions on behalf of future generations even though we are unaware of their needs. It is important to highlight that not everyone accepts this definition of SD; however, it remains the best so far [29].

To better define SE, it is crucial to understand the evolution and development of the sustainability concept and its implications for SE over time. The concept of sustainability started as an economic concern about resources reaching their capacity limit. Such a limit would impact economic growth and affect society’s welfare. Therefore, beginning with the system we want to sustain is more practical. It will end up with a different sustainability scale on the spectrum of sustainability, starting with a very weak to a very strong form of sustainability. For example, if we want to sustain the environment, we will have a strong to a very strong form of sustainability.

On the other hand, if one were going to maintain the economy (true in our case), one would have with a very weak to a weak form of sustainability. This could cause complexities between economists and environmentalists; they both talk about sustainability from different perspectives since each has a different and conflicting system to protect. Therefore, the concept of SE has evolved and shifted focus over time and across disciplines, even among economists, as evidenced by the debate between ecological and environmental economists regarding the form of sustainability.

Figure 4 attempts to summarize the evolution of the concept of sustainability over time. It shows that, before the 18th century, economic activities and functions had to be within social and environmental boundaries, which made the overall system strongly sustainable (Figure 4a). This ideal situation of SE and SD until the 18th century was not by choice but mainly due to: (a) the weakness of humankind at the mercy of nature; (b) a mostly agrarian, land- and human-power-based economy; (c) lack of technology and technological tools to overcome and use the natural capital; (d) limited utilization and demand for resources; and (e) the isolation of nations and markets since most resources were utilized for local and domestic needs. The advent of steam power, mechanization of production, technology, population growth over time, and new markets and marketing concepts created new needs, desires, wants, and consumerism psychology. All these developments led to gradual but increasing pressure on resources to increase their further utilization to meet growing demand at the expense of natural and social capital. However, with time, this growing demand for resources led to growth beyond ecological limits and created disparity in society between those who controlled and those who did not have access to resources (Figure 4b, unsustainability). The idea of sustainability first appeared in the 18th century in a book by Carl von Carlowitz, focusing on the importance of sustainable forestry as the key to long-term success in mining and all fields of livelihood [30,31]. By the mid-19th century, based on the works of many prominent economists, the idea of the limited carrying capacity of nature had emerged [32].

During the 1960s, development was thought to be equivalent to economic growth, and at the time, it was acceptable to trade off the environment for economic growth. However, by the 1970s, it was realized that economic development and the environment are interdependent [2] and that long-term environmental degradation would impact economic growth and society. Although the idea of continuous maximum production and the idea of the limited carrying capacity of the Earth were put forward in 1972 with the publication of “Limits to Growth” [33], many perceive that sustainability is the interaction between the environment, society, and economy [15] and requires a better understanding of interlinkages between the variables [34]. Therefore, between the 1960s and the 2000s, the economic sphere expanded at the expense of society and the environment, exceeding limits and causing serious challenges and threats to the system’s sustainability. As a result of technology, industrialization, capitalism aiming for continuous economic growth, and careless consumption and production at the expense of nature and social capital, there has been imbalanced growth, i.e., unsustainability (Figure 4b).

Since the 1980s, there has been a growing awareness of the importance of sustainability and balanced development in the economy, society, and environment, which has led to the concept of sustainability intending to reach a balanced SD by the 2050s (Figure 4c, weak sustainability). Thus, this shows that the concept of SE has been developing for a long time. As shown in Figure 4a, the economy was within social and ecological limits prior to the 18th century, resulting in strong sustainability (unwillingly by the force of nature on humankind). However, post 18th century, the focus on the economy outweighed social and environmental concerns, leading to increased awareness that the situation was unstainable. Therefore, there is a need for a more sustainable and balanced system that can provide development in the sustainability pillars.

Furthermore, the concept of SE has been mixed with or confused with other concepts such as Green Economy, Circular Economy, Knowledge Economy, and many more concepts of economies, as illustrated in Figure 5. These concepts do not individually represent SE; however, they could all be part of it. Therefore, these concepts could be considered the building blocks of SE.

The main objective of SE is to establish the requirements for a post-growth economy that can be sustained even in a steady-state situation. This might translate to maintaining at least minimum stock of natural capital with a low material throughput rate, which does not exceed the regenerative capabilities of the ecosystem.

As a result, an alternative, improved, and comprehensive definition of SD could be proposed as follows “a value-based, dynamic balancing process of sustaining a system that meets the needs of today’s all living species while not compromising the system’s ability to meet future needs of all living species”.

Based on the above, an alternative definition of SE could be proposed as: “a value-based, dynamic and balanced economic system that meets today’s all living creatures’ needs within ecological and social limits while not compromising the system’s ability to meet future needs of all living creatures”.

5. Conclusions

Following a comparative review and analysis of the relevant literature on SE, the paper contributes to the literature on SE by identifying core SE features and defining SE. The paper confirmed fifteen (15) features are relevant and important for SE based on the literature review and experts’ validation. The paper’s importance and originality come from the feedback and validation of sustainability experts in Qatar. Even though this research is focused on sustainability experts residing in Qatar, the conclusion could be applied beyond Qatar since the features were extracted from the literature and comparative analysis. This research could be expanded to other countries to validate the findings.

The initial list of features was presented to 32 experts in various aspects of sustainability. However, only 22 responded or participated in evaluating, modifying, and confirming fifteen (15) distinct features of SE, which is considered a valuable contribution to SE studies.

Finally, following a validated list of SE features, the paper proposes an alternative and improved definition for SE and SD. The new definition is more encompassing and could respond to new sustainability developments in the future. Furthermore, the identified features could be put to practical use by identifying or developing metrics to measure the progression of economies toward SE. A logical future step is to map the identified features against sustainability metrics to measure progress toward SE.

The limitation of this research could be the small number of experts and constrained by geographical limitation being in Qatar only. The challenge was to identify and engage sustainability experts, especially since such experts are very limited in Qatar and many of them are difficult to engage due to their commitments or lack of willingness and for other considerations.