The phrase meaning of life is younger than the steam locomotive
People have always wondered why they exist, but the English words meaning of life first appeared in Thomas Carlyle's Sartor Resartus in the 1830s. German Romantics had coined the idea a few decades earlier, as science seemed to drain the world of religious certainty. Today psychologists split the question into three measurable parts.
Carlyle's usage in 1833 and 1834 tied life's meaning to freedom and willed effort. He was probably echoing German writers: Friedrich Schlegel printed der Sinn des Lebens in his 1799 novel Lucinde, Novalis had written in a manuscript of 1797 to 1798 that only an artist can divine it, and Goethe used a related word in a 1796 letter to Schiller. These authors were reacting to modern rationalism and materialism; Carlyle pictured a torch of science scorching religion into a wilderness. Schopenhauer then posed the question outright in an essay on character, asking what purpose life serves if a person's nature is fixed from birth.
Biology offers one blunt answer. Building on the gene-centred view of evolution, George C. Williams, Richard Dawkins and David Haig concluded that if life has a primary function, it is copying DNA. Asked by Dawkins what it was all for, James Watson replied that he did not think we are for anything; we are simply products of evolution.
Psychology asks a different question: what makes lives feel meaningful? Research is converging on three linked dimensions: coherence, meaning life makes sense; purpose, having core goals; and significance, feeling one's life is worth living. Large studies of flow suggest fulfilment comes from how a hard task is tackled rather than which task it is, so that billionaires report flow only slightly more often than people with almost nothing. Terror management theory argues instead that our values largely serve to keep the fear of death at bay.
Emerging studies link a stronger sense of meaning with lower risk of Alzheimer's disease, stroke and heart attack in people with coronary disease, and with longer lives in American and Japanese samples, though these are associations rather than proof of cause. Whether life has any objective meaning at all remains without consensus, and brooding on it too much can itself signal or trigger an existential crisis.
Source: Meaning of life