I'm against this barbaric tradition of putting people in cages for whatever XYZ crimes. I think the isolation of the rest of the society from the criminals is essential but should be done in a much more humane way. For instance, prisons should be a place to learn and develop one's mind with libraries, documentaries, education and tools of creation but still making sure the person cannot contact the rest of the society. Prisoners should be making living to pay for such facilities by doing work. You might wonder what if this actually promotes more crimes but you can increase the lengths of sentences and exponentially growing lengths for repeated offenses. A way to think of prison is just another society with its own economy and rules with strict isolation but otherwise similar in most other respects. For example, a "prison town" may have cafes, restaurants, theaters etc with everything being run by this isolated community which is not allowed to be in contact with the rest. I know this is crazy and rather radical ideal but small cages and solitary confinement is inhuman beyond thought.