It is a mistake to believe that a science consists in nothing but conclusively proved propositions, and it is unjust to demand that it should. It is a demand only made by those who feel a craving for authority in some form and a need to replace the religious catechism by something else, even if it be a scientific one. Science in its catechism has but few apodictic precepts; it consists mainly of statements which it has developed to varying degrees of probability. The capacity to be content with these approximations to certainty and the ability to carry on constructive work despite the lack of final confirmation are actually a mark of the scientific habit of mind. — Freud

Although he was an atheist, I think he had a good point here.  Many atheistic scientists today, elevate science to the level of a religion.  It is to be worshiped.  It is the ONLY source of absolute ‘truth’ in the world.  It’s the only true religion for it’s advocates and believers. 

Scientists often tend not to know that their theories are psychological constructs.  They believe that certain things are ‘proven’ scientifically.  The ‘Theory of Evolution,’ is one such psychological construct.  I’ll demonstrate a psychological construct here.

We all believe that a real thing such as a chair exists in reality.  However, the problem comes in when we try to develop an objective definition of a chair.

Example 1: A chair has 4 legs and a flat surface for sitting on.

But wait, what about this…

Oops, that’s not a chair by the definition.  So we’ll revise it a bit.

2. A chair has one or more legs and a surface for sitting.

Well, there’s a problem here too.

Okay…  Let’s try again.

3. A chair is an object which is used for sitting on.

Well…  There’s a problem with this too…

Okay…  That didn’t work either.  So how to we get an objective definition of a chair.  Is it possible??  We know chairs exist.  We ‘know them when we see them.’  But how do we define them?!

Actually the notion of design gets us probably as close as we can get to an objective definition.

5.  A chair is a designed object in which the designer had the purpose in mind of designing a chair. 

So, considering the purpose of the ‘designer’ gets us a lot closer to objectively defining things in our environment.  Considering purpose and design helps to avoid many of the problems with our system of cognitive constructs.  So, evolution is a construct, and my question is, “How do you objectively define evolution?”