Sf nut here, so does that make this a no brainer question? [grin]
Yes, I believe in life on other worlds.
Not so short answer:
Life on other worlds? Yes. We are seeing evidence of this in our own solar system.
Life past single cell stage? Yes. Of course this only means plant life. Moss. Again, I believe we are seeing evidence of this already.
Intelligent life? Possibly. First, define intelligent. No, I am serious. What is intelligent? I consider my cat to be intelligent, but she would not pass an IQ test. What is considered intelligent for a human may not be for some other life form.
Human type life? Maybe. Not all live evolved the same on this planet, so I am not sure life on another world would look like us. We like to think I.L. would resemble humans, at least enough for us to identify with it. But isn’t’ that a bit … species-centric?
Life capable of traveling between stars? Maybe, but if it does exist, it is too far away for us to know. Consider that Rigel Kentaurus*, our nearest neighbor**, is over 4.3 light years away. It takes 4, almost 5 years for us to see anything from that system. Our telescopes have found no “habitable” planets within 100 light years. (to the best of my knowledge) So any inhabited worlds are well beyond 100 light years. Where was our tech 100 years ago? Primitive radio waves, which travel below the speed of light, might just now be reaching those worlds. IOW, they might just now be learning about us. Now, reverse that: SETI. You have to know where to look and what to look for. We could be staring at the evidence right now and not know it because it does not fit our definition of “intelligent”.
Should we seek it out? (cue the ST:OS theme) How about we figure out how to get around our own solar system first. [snort] We haven’t even been back to the moon since the 70’s.
Seriously, we need to learn how to get along with each other before we go trying to find new worlds. This world can’t even go one bloody damn year without starting a war/conflict somewhere. We are not ready to visit/be visited by, people who are so different from us that they may not even look humanoid.
*Please, do not tell me that you do not know what, or where, Rigel Kentaurus is.
**Yes, I know Proxima is actually closer, but it is not considered a separate system.