To insert a blank space between two paragraphs, should I use medskip and vphantom?

Question

There are at least 2 ways to insert a vertical white space between two paragraphs: medskip and vphantom. Which one should be preferred for example for spacing paragraphs in "The Chaos" poem?

Answer 1

A \vphantom does not add vertical space it adds a box of zero width, this may produce some white area on a page but it is not at all like vertical space (glue) as added \vspace and related commands. It does not stretch or shrink and crucially it is treated like text not like space at the top of a page so it is not discarded at a page break.

For special one-off spacing requirements you might want to use

<blank line>
\medskip

(where \medskip is \vspace{\medskipamount})

But any such use of explicit spacing is usually a sign that the document structures being used are not designed for the content in the current document.

The spacing between paragraphs should be controlled automatically (using the primitive \parskip parameter or the latex list parameters) so there should only vary rarely need a need to add a vertical space command in a document.

For the example here you could use verse:

\documentclass{article}

\begin{document}

\begin{verse}
Dearest \emph{creature} in \emph{creation},\\
Study English pronunciation.\\
I will teach you in my verse\\
Sounds like \emph{corpse}, \emph{corps}, \emph{horse}, and \emph{worse}.\\
I will keep you, \emph{Susy}, \emph{busy},\\
Make your \emph{head} with \emph{heat} grow \emph{dizzy}.\\
\emph{Tear} in eye, your dress will \emph{tear}.\\
So shall I! Oh hear my \emph{prayer}.

\emph{Pray}, console your loving poet,\\
Make my coat look \emph{new}, dear, \emph{sew} it!\\
Just compare \emph{heart}, \emph{beard}, and \emph{heard},\\
\emph{Dies} and \emph{diet}, \emph{lord} and \emph{word},\\
\emph{Sword} and \emph{sward}, \emph{retain} and \emph{Britain}.\\
(Mind the latter, how it's written.)\\
\emph{Made} has not the sound of \emph{bade},\\
\emph{Say-said}, \emph{pay-paid}, \emph{laid}, but \emph{plaid}.

\end{verse}

\end{document}