The following excerpt is taken from Albert Einstein: The Human Side, Selected and Edited by Helen Dukas and Banesh Hoffman, Princeton University Press, 1979.
[This] is a letter written by Einstein in response to a 19-year-old Rutger's University student, who had written to Einstein of his despair at seeing no visible purpose to life and no help from religion.
In responding to this poignant cry for help, Einstein offered no easy solace, and this very fact must have heartened the student and lightened the lonely burden of his doubts. Here is Einstein's response. It was written in English and sent from Princeton on 3 December 1950, within days of receiving the letter:
I was impressed by the earnestness of your struggle to find a purpose for the life of the individual and of mankind as a whole. In my opinion there can be no reasonable answer if the question is put this way. If we speak of the purpose and goal of an action we mean simply the question: which kind of desire should we fulfill by the action or its consequences or which undesired consequences should be prevented? We can, of course, also speak in a clear way of the goal of an action from the standpoint of a community to which the individual belongs. In such cases the goal of the action has also to do at least indirectly with fulfillment of desires of the individuals which constitute a society.
If you ask for the purpose or goal of society as a whole or of an individual taken as a whole the question loses its meaning. This is, of course, even more so if you ask the purpose or meaning of nature in general. For in those cases it seems quite arbitrary if not unreasonable to assume somebody whose desires are connected with the happenings.
Nevertheless we all feel that it is indeed very reasonable and important to ask ourselves how we should try to conduct our lives. The answer is, in my opinion: satisfaction of the desires and needs of all, as far as this can be achieved, and achievement of harmony and beauty in the human relationships. This presupposes a good deal of conscious thought and of self-education. It is undeniable that the enlightened Greeks and the old Oriental sages had achieved a higher level in this all-important field than what is alive in our schools and universities.