"... in Introduction" vs "... in the introduction"

Question

I work on a thesis, with several chapters.

Now, Chapter 1 is called Introduction. When I want to say "ABC is defined in Chapter 1", I feel I can avoid using "Chapter 1" and use "Introduction".

However, I'm not sure which is correct:

1. "in the introduction" (referring to the general concept of introductions);
2. "in Introduction" (referring to Chapter 1 by its name);
3. neither, both, or something completely different.

Answer 1

I would prefer

in the introduction

if that chapter is the introduction, or otherwise I would use

in "Introduction"

For me,

in Introduction

feels like broken English.