Do you know of any scientist who has recreated every experiment ever done or proved every science from the beginning? I don’t.
So true. Anyone who has taken a science lab course knows how hard it can be to get the “right” results which your textbook and professor say should happen. There are just so many possible sources of error. These include different measuring instruments, slightly different starting conditions, precision of instruments, human errors, etc.
And whenever a scientist gets a result that doesn’t match perfectly with theory (and I can’t think of a situation where this doesn’t happen) he has to come up with some explanation of why it doesn’t! Other than saying that he did something wrong in the experiment, one of the most common reasons is because several assumptions must be made in order to simplify things. Take the definition of an ampere for example: “
the constant current which will produce an attractive force of 2 × 10–7 newtons per metre of length between two straight, parallel conductors of infinite length and negligible circular cross section placed one metre apart in a vacuum” Can you have infinitely long wires? Two perfectly straight, perfectly parallel wires? Perfectly circular wires? Exactly one meter apart, in practice? A perfect vacuum in practice? No.
If you take away absolutely all assumptions in an experiment, you’re going to be left with a hopelessly complicated mess of calculations that won’t matter anyways because you can’t measure every quantity needed for those calculations (or perfectly for that matter).
Here’s an experiment to demonstrate what I’m saying. Try placing a marble on an incline ramp on a table from rest, letting it roll off the table, and place a marker on the floor where you predict it will land using 2-D kinematics and the force of gravity. I bet you it will not land where “science said” it will. You’ll have to assume that friction was at work on the ramp, that the marble was not a perfect sphere, that air resistance was in effect, that you didn’t use the exact acceleration of gravity for your elevation above sea level, that you didn’t measure the height of the table or the length and angle of the ramp perfectly, etc. Even if the marble does land on the marker, that doesn’t prove anything. You’ll have to set up the same type of situation over and over again, at different locations, elevations, temperatures, humidities, air pressures, different materials for ramps, different heights of the table, etc., and even then, you can’t try every possible situation imaginable, which would be necessary to “prove” what the science asserts.
“Consistent evidence?”
Sort of. There may be consistent
qualitative evidence, but any talk of consistency with
quantitative evidence has to be defined within a certain precision and error. And like Buffalo said, no scientist can perform every experiment and know all the math for himself. He has to hold on faith that other scientists are doing their job honestly and correctly.
Science in practice is SO much different than science in theory (which is essentially math), and a lot of blind followers of Richard Dawkins don’t realize this.