diff --git a/ipynb/lispy.ipynb b/ipynb/lispy.ipynb
index ab2b2a6..c6d5dc3 100644
--- a/ipynb/lispy.ipynb
+++ b/ipynb/lispy.ipynb
@@ -100,7 +100,7 @@
    "source": [
     "## The core of Lisp: eval \n",
     "\n",
-    "Here is the core of the interpreter, `eval`. It takes as input an expression, `exp`, and an **environment** that specifies the values of variables. It returns the value of the expression. These few lines are what  what [Alan Kay called](https://queue.acm.org/detail.cfm?id=1039523) \"the Maxwell's Equations of Software.\"\n"
+    "Here is the core of the interpreter, `eval`. It takes as input an expression, `exp`, and an **environment** that specifies the values of variables. It returns the value of the expression. These few lines are what [Alan Kay called](https://queue.acm.org/detail.cfm?id=1039523) \"the Maxwell's Equations of Software.\"\n"
    ]
   },
   {
@@ -117,7 +117,7 @@
     "            return exp\n",
     "        case Symbol():                             # variable evaluates to its value in environment\n",
     "            return env[exp]\n",
-    "        case ('define', Symbol(name), val):                # definition adds name to the environment\n",
+    "        case ('define', Symbol(name), val):        # definition adds name to the environment\n",
     "            env[name] = eval(val, env)\n",
     "            return name\n",
     "        case (proc, *args):                        # procedure call\n",