In the context of exploring the existence or otherwise of a purpose to (or in) the universe, it may be useful to define certain terms.  I shall therefore attempt to clarify some of the controversies in the framework of the definitions below:

Mechanism:  will refer to the modus operandi of a complex system which functions in accordance with a set of rules, principles, and laws.  The functioning of a mechanistic system is visualizable directly, through analogies, or in a mathematical sequence of reasoning.

Goal:  will mean a point or a state towards which the activities of a system seem to tend.

Purpose:  the reason why a system functions in order to reach a goal. It is important to recognize that while a careful external observer may be able to infer the goal of system on the basis of its behavior, he/she cannot always fathom the purpose.  It is only the system itself which may be aware of the purpose.  This is most obvious in the case of human activity.  We can determine what some people are after, but may not know why (for what purpose) they are after it.

It is essential to recognize this difference between goal and purpose. The goal of a student may be to graduate with a good degree.  The purpose of this goal may be to obtain a good job, to impress his parents, to satisfy a longing, or whatever.  Only the student knows it well. If getting a good job is the goal, then the purpose of that goal is to lead a good life, to repay a loan, to raise a family, and so on.

From this perspective, we note that there may be a goal without a purpose, but there cannot be a purpose without a goal.  Thus, for example, the goal of a body thrown in a field of force may be to occupy the state of minimum potential energy, but there may be no reason for it to do that.  On the other hand, if the goal of a plant is to go towards sunlight, the purpose may be to continue to live.

Purposeful activity is more sophisticated than goal-directed activity, because it implies an awareness of the striving towards a goal.

The factors enabling a system to achieve its goal(s) are of two kinds: (a) E or extrinsic, i.e. in the world beyond its own control; (b) I or intrinsic, i.e., within itself: internal elements that may modify the course of action.  The essential difference between the animate and the inanimate world may lie in this:  that in the inanimate world, the E-factors alone count; whereas in the animate world, I-factors also come into play. The more sophisticated a bio-entity is, the greater is the dominance of the I-factors.

The goal of every life form seems to be its own continuation for the maximum length of time possible.  The purpose for this goal may be related to the conscious or unconscious satisfaction the entity experiences in living.

The goal of inanimate systems seems to be the non-violation of any of the basic principles and laws undergirding the physical universe.

What about the universe as a whole? The scientific study of the phenomenal world seems to suggest that the cosmos is mechanistic in so far as it functions on the basis of rules and principles and laws.  Its goal seems to be the stability of the universe for an extended period of time. On the basis of human understanding of the functioning of the universe, no purpose seems evident for this goal.

This is not surprising because, as I noted earlier, an external observer cannot always fathom the purpose for the goal which a system is striving to reach.  This is the reason why human minds (by their analysis) have not been able to discern any purpose for the universe.  It does not follow from this that there is no purpose.

It is possible to hypothesize some purpose to the universe, such as, for example, the emergence and continuation of the human species.  There is no a priori reason why this may not be true, though there do not seem to be overwhelming evidence for this.

Herein lies the important difference between religion and science. (Most) religions affirm that there is a purpose to the universe, and to human life.  Science says that on the basis of its own accumulated data there does not seem to be any such purpose.  I suggest that the purpose of the universe, enunciated by religions may, but need not, be correct, whereas science may never be able to unravel any such purpose.

It is important to recognize that the cautious contention of science does not contradict the firm conviction of religion.

It is entirely possible that the purpose of the universe is to make it all entertaining and enjoyable for a brief interval of time (in cosmic history) for a select group of highly evolved brain-bearing entities called humans.  Some have argued that this is a wasteful effort, considering the eons it took these creatures to evolve, and the short period during which the overall effects will be enjoyed and appreciated.  But then, consider a movie that is made:  expending lots of money and over a period of a year or more.  All for what?  Just for a couple of hours of enjoyment for some people (those who see that movie). Why cannot a similar thing be true with the universe also?