The question of the justification of existence is a profound and multifaceted inquiry that has been a central concern in various philosophical traditions. One prominent theme across several sources, particularly those rooted in existentialism, is the apparent lack of an inherent, external justification for human existence. Jean-Paul Sartre, in _Being and Nothingness_, posits the concept of the "for-itself" (consciousness) as a being that "is not what it is and which is what it is not". This points to a fundamental contingency, where the for-itself exists but without a pre-ordained essence or reason for being. Sartre states that the for-itself is "thrown into a world and abandoned in a 'situation'", and the question "Why is this being exactly such and not otherwise?" can be posed to it, just as it can be for things in the world. This inherent contingency leads to a feeling of gratuity, where the for-itself apprehends itself "as being there for nothing, as being de trop". Similarly, Søren Kierkegaard, through the voice of a "Nameless friend" in _Repetition and Philosophical Crumbs_, expresses a deep loathing of an existence deemed "insipid, without salt or meaning". The individual feels "thrust into the ranks as if I had been forced" without being informed of the rules or asked for consent, questioning the very grounds and management of "this great enterprise called actuality". Todd May, in _A Fragile Life_, suggests that a proper starting point for considering existence is "their existence itself, which requires neither affirmation nor regret". He argues for an acceptance of existence as a condition for even asking questions about our relation to the past. This perspective acknowledges existence as a given, perhaps sidestepping the need for an external justification and focusing instead on how we relate to it. However, the desire for justification remains a powerful human impulse. Sartre argues that consciousness perpetually pursues the project of "being God," a being whose justification is included in its very existence, as a way to flee from its inherent contingency. This "God-project" signifies the desire for self-causation, to be the foundation of one's own being. Yet, Sartre details the inconsistencies and contradictions inherent in this project. In contrast to the existentialist emphasis on contingency, theological perspectives often provide a justification for existence grounded in a divine creator. Athanasius, as discussed in _Atonement: A Guide for the Perp_, argues that it is "monstrously unfitting for the Creator that his creature fail to attain its end". Humankind's purpose, according to this view, is "to know, love and worship its Creator". The very act of creation implies a desire from God to be known by his creation. Similarly, the Nyāya Vaiśeṣika school of Indian philosophy, as outlined in _An Introduction to Indian Philosophy_, offers causal arguments for the existence of God, proposing that all composite objects must have a cause, leading ultimately to an uncaused cause. Descartes, in his _Meditations_, also provides arguments for the existence of God, suggesting that the idea of a supremely perfect being within us could only have originated from such a being. He contends that existence is contained in the very concept of God as a necessary and actual being. Descartes also argues that our inability to preserve ourselves implies dependence on a being that does have the power of self-preservation, which he identifies as God. Spinoza, as discussed in _The Rationalists_, similarly argues that for each individual existent thing, there must be a cause for its existence, and ultimately, the cause of existence for substance lies within its own nature, implying a single, self-caused substance, which can be understood as God. Kant, while critical of traditional metaphysical proofs of God's existence, introduces the concept of human dignity as an intrinsic worth that necessitates treating individuals as ends in themselves, not merely as means. While not directly a justification for existence itself, this underscores the inherent value of rational beings. Todd May, in _Should We Go Extinct?_, explores Kant's view, noting that while reason in the world is considered good, it doesn't necessarily mandate the continued existence of human beings specifically. However, May discusses how the instrumental value of human beings in areas like sentience and rationality, as argued by Sarah Buss, could provide a reason for treating us as ends-in-ourselves, thus indirectly supporting continued existence. The question of meaning is closely intertwined with the justification of existence. If existence lacks inherent justification, individuals often seek to create or discover meaning to give their lives purpose. Todd May, in _A Significant Life_, differentiates between asking "What is the meaning of life?" as if it were a discoverable entity within the universe, and asking about the "meaningfulness of life," which involves the values and assessments that make a human life worthwhile. He suggests that the goal in reflecting on meaning is to confront the trajectory of our lives with the question of their significance, without relying on cosmic support. Existentialist thinkers often emphasize the role of freedom and choice in creating meaning in an absurd world. Authenticity, as discussed in _The History and Ethics of Authenticity_, is presented as an ethical ideal through which individuals can orient their actions and grant meaning to an existence without pre-determined essence. This socio-existential approach emphasizes choice, commitment, and becoming what one is as dimensions of authentic living that can provide a sense of meaning. The concept of "reason" itself is examined as a potential ground for justification. Karl Jaspers, as discussed in _Existentialism From Dostoevsky To Sartre_, posits the problem of "reason and Existenz," not as an antithesis but as a connection where reason, in its Kantian scope of clarity and truth, intersects with [[Existenz]], which delves into infinite depths beyond determinate knowledge. Reason, according to Jaspers, is oriented towards Existenz, providing clarity and receiving content in return. Existenz, in turn, is oriented towards Transcendence. This interplay suggests that reason, while not providing a direct justification for existence, is crucial in understanding and navigating it. David Bentley Hart, in _The Experience of God_, questions the assumption that nonexistence is a more natural state than existence. He argues that the real mystery is not why there is something rather than nothing, but how any contingent reality can exist at all. Hart suggests that even abstract possibilities must exist in some kind of reality, implying a fundamental source of actuality. This perspective shifts the focus from justifying existence to understanding the very nature of being and actuality. In conclusion, the justification of existence is a complex issue with no single, universally accepted answer within the provided sources. Theological perspectives often ground justification in a divine creator and purpose. Existentialist viewpoints highlight the inherent contingency and absurdity of existence, emphasizing the individual's freedom and responsibility to create meaning. Kantian ethics focuses on the intrinsic dignity of rational beings, providing a moral framework that implies the value of human existence. Ultimately, whether existence requires justification, and what might constitute such a justification, remains a central and ongoing question in philosophy.