Is it better to play with a computer or a human

I just bought Houdini 4 Aquarium and I am playing against it with a skill handicap. I have set the engine's strength to 1800 ELO and I have yet to win a single game.

What in your opinion are the pros and cons of playing against a computer or a human. I feel that playing with a computer is good because

1.)It is the real test of the lines that you play.

2.)You can take your time to calculate as opposed to 3 min blitz online where you just cannot sit and think anything.

It's better to play against people. The reason is simple: A person, especially one stronger than you, can help to explain your mistakes. You're more likely to get someone to go over the game if it was OTB.

Both have their advantages.  To me, the chess engines do, as you say, analyze my play at the single move level and that sometimes helps me see where I'm going wrong.

Additionally, I have Chess King Standard with Houdini 2 (I didn't see the need to get something better than 3000+ rating) and it does have an immense database that lets me see what othe human players did from certain positions.  Win or Lose, i can't wait to see what else I could have done with my current daily Caro-Kann defense.

But, but far the most useful chess engine to me is the freebie Lucas Chess, which comes with world-computer-champ Stockfish 8 as well as a lot of other chess engines over which you have controls by ranking, ELO 200-3300 or set it to match your level of play or a little better or worse, by forced openings if you want, by hints of no hints, by personality (reckless, solid, etc.), you can have it choose the engines best calculated move (at that rating), randomly from among the engine's highest choices, or randomly from among the not-so-best choices, and you can set it so it takes much less time than you to think if you want to shorten the game a little without turning it into a blitz.

That way, when trying out a new opening, I get to see unexpected moves that make me think about the ideas behind the opening and by the time I'm ready to play it against humans, I already feel comfortable with it.

But for true variety and dealing with the thrill and tension of real play, there's nothing like human opponents.

If you're lucky enough to play against strong players, you can also get a better analysis that Stockfish, Houdini, etc. can't give like, "You should not have attacked on the King-side because you didn't have material or positional superiority. You should have moved your knight to the excellent outpost at c5 and attacked up the middle with a Pawn Storm because...."

Which do you think is more instructive:

Chess engine: white is +.4

Chess teacher: your position is slightly better due to the activity of your pieces, and black has a backward pawn on e6.

"I have set the engine's strength to 1800 ELO and I have yet to win a single game."
Implying you are not at that strength or maybe the engine has database selected the opening and you come out of the opening with a less than equal position all the time.

It seems to me that if an engine describes a position as +.4 then a player should have the ability to look at the strengths and weaknesses of both sides until the positional considerations of the eval are clear.
If truly clueless then use the Fen of the position and literally move the pieces to different squares  until the eval of the position changes.
https://www.youtube.com/watch?v=V1lvu6j4LLM&list=TLGGki4fwcPU8gYyOTAzMjAxNw
Ben Finegold - Alejandro Ramirez
There are some great points in that game where Ben tells the audience what the engine "thinks".
A suggestion of Bc4 does not sit well with Ben.

@ihatelosingman --- I learned chess with two boards and Fischer's 60 Games. The second board was to play out the variations he included.
Does your best move engine back up the move with a variation, if so do the same and then look at two boards until you can see the point the engine was making.

@Rat1960 - you seem to have dismissed the possibility that the OP has drawn all of these games

The advantage of playing the computer is that it should at least play consistently at the strength you set it to. Although I find that dumbed-down engines are disproportionately strong in complicated tactical positions

One problem with playing against a computer is that it's almost impossible to win. Even Kasparov was soundly crushed by IBM's Big Blue when they played and that was 20 years ago, although he won a few times. So it's kind of demoralizing to keep losing. Playing against humans means more wins, which makes it more fun. Which is good.

Helpful  

https://youtu.be/1yAgspiRnvM

In this video GM Roman Dzindzichashvili instructs his students not to play against Chess computers click on the link to see why  

Honestly, I believe playing against the engine is best training tool. As long as one can swallow the losing streak. If one manage to play up to 40 moves without getting mated, that is good. 50 moves... better. 60 moves... Expert!

All things equal, I think it is better to play against people if your aim is to compete in tournaments.

All things are never equal. In particular, it is generally much easier to find computer opponents that are willing to sit through long games. I also like how against some computers, you can set the level up in increments as you get better so that you are playing against something that is a little stronger than you are. You can't do that with people anywhere near as easily. Computers are also consistent. They don't have good and bad days (although they do have good and bad positions).